#define _CRT_SECURE_NO_WARNINGS 1

#include<stdio.h>

int main() {
	int count = 1;
	for (int i = 10; i <= 100; i++) {
		if ((i % 10) % 9 == 0 && i % 10 != 0) {
			count++;
			if ((i / 10) % 9 == 0)
				count++;
		}
	}
	printf("%d", count + 10);
	return 0;
}